(a) Field of the Invention
This invention relates to a structure of a synchronizing piece to synchronize the turning operations of a plurality of indicating leaves appearing in an indicating window in a leaf type indicating device and a method of fitting the same.
(B) Description of the Prior Art
In some leaf type indicating device, different contents can be successively shown in an indicating window by turning successively a plurality of indicating leaves arranged in a lateral direction. However, depending on the use of the indicating device, it is necessary to make the device so that a pair of leaves adjacent to each other may turn simultaneously at constant time intervals. A leaf type digital clock is a typical example requiring such function. That is to say, in the leaf type digital clock, it is necessary that the hour indication should be advanced by one step by turning the leaf indicating the hour digit simultaneously with the change from "59" to "00" by the turning of the leaf indicating the minute digit. In a conventional digital clock of this type, in order to attain such object, as shown in FIG. 1, a synchronizing piece 11' having a side portion 11'a with which a lug 4'a.sub.1 of a minute indicating leaf 4'a can contact, a bent portion 11'b for temporarily locking an hour indicating leaf 6', a hole portion 11'c through which a main shaft 10' rotatably supporting a minute indicating drum 5' and an hour indicating drum 7' passes and an end portion 11'd inserted in a hole 1'a formed in a body frame 1' is provided between the minute indicating drum 5' pivotally supporting a minute indicating leaf group 4' including at least the one minute indicating leaf 4'a provided with the lug 4'a.sub.1 on the side edge and rotating at a comparatively high speed and the hour indicating drum 7' pivotally supporting an hour indicating leaf group 6' and rotating at a comparatively low speed. The synchronizing piece 11' is so made as to be supported by inserting the main shaft 10' through the hole portion 11'c and to be held in a fixed position by inserting the end portion 11'd into the hole 1'a in the body frame 1'. However, in such arrangement of the synchronizing piece 11', the main shaft 10' must be passed through the hole portion 11'c of the synchronizing piece 11' and therefore, in assembling the device, the synchronizing piece 11' has had to be incorporated together with the two indicating drums 5' and 7'. Usually, there are further many working steps after this incorporating work and the synchronizing piece 11' is made of a very thin resilient material because the turning force of the minute indicating leaf 4'a is small.
Therefore, there has been a defect that the synchronizing piece 11' will be likely to be deformed in the assembling step. In order to dissolve these defects, there has been already suggested a method wherein the synchronizing piece 11' is fixed to the body frame 1'. However, with such method, there is a play in the axial direction of the minute and hour indicating drums 5' and 7' and therefore there has been a defect that their relative positions in the axial direction will slip and the synchronizing operation will become indefinite.